JPH10282144A - Probe unit for testing flat-plate-shaped body to be inspected - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a protrusion from being released from a wiring part by covering an area other than the tip of the protrusion and a close wiring part with an electrically insulated protection layer. SOLUTION: On testing, a probe unit 20 and a body to be inspected are relatively pressed while the exposed part of a protrusion is in contact with the electrode part of the body to be inspected. As a result, each probe region 32 is warped in an arc and a protrusion 34 is rubbed against the electrode part. At this time, a friction force for releasing the protrusion 34 from a wiring part 24 is operated between the protrusion 34 and the electrode part. However, since the protrusion 34 and the wiring part 24 are protected while the tip of the protrusion 34 projects by a protection layer 30, the protrusion 34 cannot be released and fall from the wiring part 24 and the wiring part 24 cannot be released from the non-conductive member 22 near the protrusion 34. Further, the entire wiring part 24 cannot be released from the non-conductive member 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a probe unit used for testing the electrical characteristics of a flat test object such as an integrated circuit.

[0002]

2. Description of the Related Art An integrated circuit on a semiconductor wafer, an integrated circuit separated from a semiconductor wafer into a chip, and an integrated circuit on which a chip has been mounted are subjected to an energization test to determine whether the circuit operates according to specifications. Is done. This kind of energization test is performed by measuring electrical characteristics using a test head, ie, a test head, which is called a probe board, a probe card, or the like.

[0003] A test head of this kind comprises a plurality of probe elements which are electrically connected to the electrical connection pads or electrodes of the integrated circuit. The probe element is an electrical insulating film such as an aluminum oxide of an electrode portion such as a connection pad of an integrated circuit so that a high-frequency signal can be reliably applied to the integrated circuit and a corresponding electric signal can be reliably obtained from the integrated circuit. It is required to have a function to break through.

[0004] The above requirements are generally achieved by a so-called rubbing action, in which the surface of the electrode is rubbed with the tip of the probe element. Such a rubbing action causes the probe section to press slightly slightly with the electrode section of the integrated circuit and the tip of the probe element in contact with each other, thereby causing the probe element to warp due to such overdrive, thereby causing the integrated circuit to be deformed. This is caused by relatively displacing the contact portion between the electrode section and the tip of the probe element.

As one of the test heads used for this kind of energization test, there is a type using an elastically deformable film-shaped probe unit (for example, Japanese Patent Laid-Open No.
No. 363671).

This film-like probe unit forms a wiring pattern on an elastically deformable film-like wiring substrate by a so-called printing wiring technique such as a photolithography method or a printing wiring method used for manufacturing an integrated circuit. A plurality of slits for separating the wiring portion of the wiring pattern into a finger shape are formed in the wiring substrate, and a part of each wiring portion is used as a probe element, and a bump, that is, a projection is formed therein.

More specifically, the film-shaped probe unit has a plurality of linear sheet-shaped non-conductive members disposed on one surface of a sheet-shaped spring member by coating, bonding, or the like. A wiring pattern having a wiring portion is formed on a flexible non-conductive member, and a plurality of slits forming an elongated region including at least one wiring portion forming a probe element are formed on the spring member and the non-conductive member. Thus, a plurality of finger-shaped probe regions are formed, and projections are formed at the tips of the probe elements by plating, bonding, or the like.

[0008] This type of film probe unit is
After attaching the probe mounting body to the probe mounting body with an adhesive, the probe mounting body is mounted on a plate-like wiring board with an appropriate mounting tool, thereby assembling a test head. It is used in a state where it is pressed against an appropriate electrode part.

According to the above-mentioned film-shaped probe unit, the wiring section and the probe area can be manufactured by the printed wiring technique, and therefore, compared to a plate-shaped head using a probe unit using a plurality of probes manufactured from metal wires. It will be cheaper.

However, in the conventional film probe unit, the probe element warps due to overdrive,
Due to the fact that the projections rub against the electrode portions of the integrated circuit, the projections may come off from the wiring portions, resulting in the need to interrupt the test.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to prevent a projection from peeling off from a wiring portion.

[0012]

According to the present invention, a probe unit used for testing a flat object to be inspected according to the present invention is formed with a sheet-like non-conductive member and one surface of the non-conductive member at an interval. A wiring pattern including a plurality of elongated wiring portions, a sheet-like spring member disposed on a portion corresponding to at least one end of the wiring portion on the other surface of the non-conductive member,
A conductive protrusion protruding from one end of each wiring portion to the side opposite to the spring member; and an electrically insulating protective layer covering the protrusion and at least the wiring portion near the protrusion in a state where the tip of the protrusion protrudes. And

The protective layer is provided on the other surface of the non-conductive member so as to cover the protrusion and at least the wiring portion near the protrusion. The protrusion has a tip protruding from the protective layer and exposed outside the protective layer. The probe element is formed by a part of a wiring portion having a projection.

During the test, the exposed portion of the projection is brought into contact with the electrode portion of the test object and pressed. The probe area, which includes one or more probe elements, bows in an arc, so that the protrusions rub against the electrodes. At this time, a frictional force that peels off the protrusion from the wiring portion acts between the protrusion and the electrode portion.

However, since the projection and at least the wiring portion near the projection are protected by the protective layer so that the tip of the projection protrudes, there is no possibility that the projection is peeled off from the wiring portion, and the wiring portion is located near the projection. There is no risk of peeling off from the non-conductive member in the above.

According to the present invention, since the protrusion and at least the wiring portion near the protrusion are covered with the electrically insulating protective layer so that the tip of the protrusion protrudes, the protrusion is prevented from peeling off from the wiring portion. In addition, the wiring portion is prevented from being separated from the non-conductive member in the vicinity of the protrusion.

The protective layer can cover the protrusion and at least a portion of the wiring portion that functions as a probe element. With this configuration, even if the probe region is warped due to overdrive, the wiring portion acting as the probe element is prevented from being peeled off from the non-conductive member.

[0018] Further, it may include at least a plurality of slits formed in the spring member to form a plurality of elongated probe regions including one or more of the wiring portions.
This way, each probe is completely independent,
As compared with the case where the probe regions are not independent, the protrusion surely contacts the electrode portion of the device under test.

In addition, it may include one or more conductor layers disposed within the protective layer. In this way, by connecting the spring member and the conductor layer to a portion at the ground potential, leakage of electric signals between adjacent probe elements and mixing of electric noise into each probe element are significantly reduced.

In a preferred embodiment, the semiconductor device further includes a second wiring pattern including a plurality of elongated second wiring portions formed on the protective layer so as to extend in parallel with the probe element;
A conductive second protrusion protruding from one end of each second wiring portion to the side opposite to the spring member; and the second protrusion and the second protrusion in a state where a part of the second protrusion protrudes. An electrically insulating second protective layer covering the wiring portion.

In the embodiment having the conductor layer, the protective layer includes the first electric insulating layer covering the protrusion and the wiring portion in a state where the protrusion penetrates, and the protrusion and the conductive layer in a state where the tip of the protrusion protrudes. A second electrically insulating layer covering the body layer. The conductor layer is formed on the first electrically insulating layer, and has a portion corresponding to a position where the spring member is arranged (particularly, a probe region).

Each of the protrusions can penetrate the conductor layer while maintaining the electrical insulation state, thereby preventing the wiring portion from being short-circuited by the conductor layer. The conductor layer can be electrically connected to the spring member, so that the conductor layer can be maintained at the ground potential during the test. The conductor layer can be penetrated through the wiring portion while maintaining the electrical insulation state, and can be maintained at the ground potential during the test. Each probe region can include a plurality of wiring portions.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 to 3, a film-shaped probe unit 20 has a non-conductive member 22 formed of a flexible sheet made of an electrically insulating material such as a polyimide resin. A wiring pattern having a plurality of wiring portions 24 formed on one surface of the non-conductive member 22; a sheet-shaped spring member 26 disposed on the other surface of the non-conductive member 22; And a protective layer 30 made of an electrically insulating material surrounding the wiring pattern.

The non-conductive member 22 is formed into a flexible sheet by an appropriate method such as coating an electrically insulating material on one surface of the sheet-like spring member 26. It is fixed. However, the flexible electrically insulating sheet member and the spring member 26 are
It may be fixed by an appropriate method such as adhesion or welding.

The wiring pattern is formed on the other surface of the electrically insulating member, that is, the non-conductive member 22, by a so-called printed wiring technique such as a photolithography method or a printed wiring method. Each wiring portion 24 extends linearly from one end edge of the non-conductive member 22 between adjacent probe regions 32. Each wiring section 24
Has a projection 34 formed at its tip by an appropriate technique such as nickel plating.

In the illustrated example, the projections 34 are like studs,
It has a hemispherical tip and a cylindrical main body following the tip. In the illustrated example, each protrusion 34 is a hemispherical protrusion or bump formed by nickel plating. However, the protrusion formed in a predetermined shape in advance may be fixed to the wiring portion 24 with a conductive adhesive. Each wiring section 2
The pair of 4 and the projection 34 provided on it serves as a probe element.

The spring member 26 is formed of a thin conductive leaf spring material such as a stainless steel plate, a copper plate, a brass plate, a beryllium plate, and is overlapped with the non-conductive member 22. The spring member 26 is, in the illustrated example, a non-conductive member 22.
Are arranged on one entire surface. However, the spring member 2
6 only needs to be arranged at least at the part of the non-conductive member 22 corresponding to one end of the wiring part 24.

Each slit 28 divides the non-conductive member 22, the wiring pattern 24, the spring member 26, and the end side of the protective layer 30 into a plurality of finger-shaped probe regions 32 including the wiring portion 24. It is formed so as to penetrate the probe unit 20 by a cutting process using an appropriate means such as a photolithography method or a laser beam cutting method. Each slit 28 extends from one end edge of the probe unit 20 to between the wiring portions 24.

In the illustrated example, the protection layer 30 has the protrusions 34 and the wiring pattern 24 in a state in which only the protrusions protrude, that is, covers the outer peripheral portion of the hemispherical surface.
Is formed on the other surface of the non-conductive member 22 by an appropriate method such as coating, application, printing, or the like.

However, the protective layer 30 has a projection 34 and at least a portion of the wiring portion 24 near the projection, preferably at least a portion of the wiring portion 24 in the probe region 24, so as to cover the outer peripheral portion of the hemispherical surface. May be formed so as to cover.

Each probe region 32 is formed by a non-conductive member 22, a spring member 24, a protective layer 30, a wiring portion 24 and a projection 34 in an elongated region defined by a slit 28. In the illustrated example, each probe region 32
The range includes a part of one wiring part 24 and therefore includes one probe element. However, each probe region 3
2 may be a range including a plurality of wiring portions 24 so as to include a plurality of probe elements.

In the illustrated example, five slits 28 and 6
Although only one wiring portion 24 and six probe regions 32 are shown, the probe unit 20 actually has more slits, wiring portions, and probe regions.

As shown in FIGS. 4 and 5, an inspection head using the probe unit 20, that is, a test head 40, includes, for example, a plurality (four in the illustrated example) of probe units 20 attached to the probe mounting body 42. The probe mounting body 4 is mounted by an appropriate mounting means such as an adhesive.
2 with an appropriate fixture such as a ring plate 44,
By attaching to a wiring board 46 using an electrical insulating plate, assembly can be performed.

When assembled to the test head, each wiring section 24 is electrically connected to a wiring section (not shown) formed on a wiring board 46 for supplying a test electric signal, and the spring member 26 is grounded. Connected to a potential site.
As a result, leakage of an electric signal between adjacent probe elements (wiring portion 24) and mixing of noise into each probe element are reduced.

During the test, the probe unit 20 and the device under test are relatively pressed while the exposed portions of the projections are in contact with the electrodes of the device under test. Accordingly, each probe region 32 is warped in an arc shape, and the protrusion 34 rubs the electrode portion.
At this time, a frictional force acts to separate the protrusion 34 from the wiring portion 24 between the protrusion 34 and the electrode portion.

However, since the projections 34 and the wiring portions 24 are protected by the protective layer 30 so that the tips of the projections 34 protrude, there is no possibility that the projections 34 will be peeled off from the wiring portions 24 and the wiring portions 24 will not be projected. Is not likely to be peeled off from the non-conductive member 22 in the vicinity of the non-conductive member 22, and there is no possibility that the entire wiring portion 24 is peeled off from the non-conductive member 22.

In particular, when the outer peripheral portion of the hemispherical surface of the projection 34 is covered with the protective layer 30 as in the embodiment, even if a large frictional force acts on the projection 34 and the electrode portion, the projection 34 is not affected.
Is not likely to be peeled off from the wiring portion 24. However, without protecting the outer periphery of the hemispherical surface of the protrusion 34 with the protective layer 30, the protrusion 34 is formed such that the outer periphery of the columnar main portion of the protrusion 34 is sandwiched (that is, wrapped around) by the protective layer 30. May be protected by

When the probe unit 20 and the device under test are relatively pressed, each probe area 32 is independent of the other probe areas 32 because the slit 28 exists between the adjacent probe areas 32. Bend. For this reason,
As compared to the case where the probe region 32 is not independent,
4 surely comes into contact with the electrode portion of the test object.

The probe unit 20 includes, for example, a sheet-shaped non-conductive member 22 and a sheet-shaped spring member 26 arranged in a state where the spring member 26 is fixed to one surface of the non-conductive member 22. A wiring pattern including a plurality of wiring portions 24 is formed on the other surface of the conductive member 22, and each wiring portion 24
A protrusion 34 is formed at one end of the probe unit 20 on the side opposite to the spring member 26, a protective film 30 is formed on the other surface of the non-conductive member 22, and a plurality of slits are formed at one end of the probe unit 20. And one end thereof is connected to a plurality of probe regions 32.
It can be manufactured by dividing into

Instead of forming the non-conductive member 22 on the spring member 26 by coating, the non-conductive member 22 may be formed on the sheet-like spring member 26 by a coating technique, a printing technique, or the like. May be formed on the sheet-like non-conductive member 22 by a printed wiring technique, a vacuum deposition technique, or the like.

In the above embodiment, one probe region 3
Although one probe element is formed in two, a plurality of probe elements may be formed in one layer or in a plurality of layers in one probe region 32. Further, a single conductor layer or a plurality of layers may be formed in each probe region 32 for the conductor layer connected to the ground.

The probe unit 50 shown in FIGS.
Has a plurality of probe elements formed in two layers or a plurality of layers in the probe region 32. The probe unit 50
Further, a second wiring pattern including a plurality of elongated second wiring portions 52 formed on the protective layer 30, and a conductive pattern protruding from one end of each second wiring portion 52 to the side opposite to the spring member 26. And a second protection layer 56 that surrounds the second protrusion 54 and the second wiring portion 52 in a state where a part of the second protrusion 54 protrudes.

Each second wiring section 52 is connected to the probe region 32
In parallel with the first wiring portion 24,
Extends from one edge of the protective layer 30. Second wiring section 5
The pair of the second and second projections 54 acts as a second probe element. The protrusion 54 has an outer peripheral portion of the hemispherical surface covered with the protective layer 56 and has a tip protruding from the protective layer 66. The second wiring portion 52, the second protrusion 54, and the second protection layer 56 may be formed in that order in the same manner as the first wiring portion 24, the first protrusion 34, and the first protection layer 30. it can.

The probe unit 60 shown in FIGS. 9 and 10 has a conductor layer 62 connected to the ground. Each probe region 32 includes a pair of wiring portions 24 extending parallel to the longitudinal direction thereof, and a conductor layer 62 including a pair of probe elements formed by a projection 34 attached to an end of each wiring portion 24. Embedded in the protective layer 30.

The protective layer 30 includes a first electric insulating layer 64 covering the wiring portion 24 and a second electric insulating layer 66 covering the protrusion 34 and the conductor layer 62. The conductor layer 62 is formed on the first electric insulating layer 64. Each protrusion 34 has a hemispherical tip and a columnar main body following the tip, and completely penetrates the first electrical insulating layer 64 and has a semispherical surface. The outer peripheral portion is formed by a second electric insulating layer 66.
And the tip protrudes from the second electrical insulating layer 66.

The conductive layer 62 and the first and second electric insulating layers 64 and 66 are formed of the first electric insulating layer 64 and the conductive layer 62.
And the second electrical insulating layer 66. The conductor layer 62, together with the spring member 26, is later connected to a portion at a ground potential (not shown). As a result, leakage of electric signals between adjacent probe elements, particularly between the wiring portions 24, and mixing of electric noise into each probe element are significantly reduced.

However, as shown in FIG. 11, the conductor layer 62 is connected to the spring member 26 by a conductive short-circuit member 68 penetrating the first electric insulating layer 64 and the conductor layer 62,
The spring member 26 may be connected to an unillustrated ground potential portion. In this case, the short-circuit member 68 is maintained by a part of the first electric insulating layer 64 so as not to contact the wiring portion 24.

In the probe unit 70 shown in FIGS. 12 and 13, a plurality of conductor layers 72, 74, and 76 for maintaining the surroundings of the wiring portion 24 at the ground potential are provided on the protective layer 30. The conductor layers 72, 74, 76 extend from one end edge of each probe region 32 beyond the probe region 32 in the longitudinal direction of the probe region 32.

The conductor layers 72 and 74 are arranged so as to extend parallel to the wiring portion 24 at positions facing each other with the wiring portion 24 interposed therebetween.
It is formed on the non-conductive member 22. On the other hand, the conductor layer 76 is formed in the protective layer 30 so as to extend from the wiring portion 24 and the conductor layers 72 and 74 on the side opposite to the spring member 26 at a distance and in parallel with the spring member 26. .

The protection layer 30 includes a first electric insulation layer 78 covering the wiring portion 24 and the conductor layers 72 and 74, and a second electric insulation layer 80 covering the protrusions 34 and the conductor layer 76. The conductor layer 76 is formed on the first electric insulating layer 78. The projection 34 has a hemispherical tip portion and a columnar main portion following the tip portion. The projection 34 completely penetrates the first electrical insulating layer 78 and has a tip portion which is electrically connected to the second electrical insulating layer 78. It protrudes from the layer 80.

The conductor layers 72, 74, and 76 are formed of the spring member 2
6 together with a portion of the ground potential (not shown). As a result, leakage of electric signals between adjacent probe elements, particularly between the wiring portions 24, and mixing of electric noise into each probe element are significantly reduced.

However, as shown in FIG. 12, the conductor layer 76 is connected to the spring member 26 by a conductive short-circuit member 82 penetrating the first electrically insulating layer 78, the wiring portion 24 and the non-conductive member 22. Alternatively, the spring member 26 may be connected to a ground potential portion (not shown). In this case, the short-circuit member 82
The first electric insulating layer 78 is so formed as not to contact the wiring portion 24.
Maintained by some of the The other conductor layers 72 and 74 also
A similar pin may be connected to the spring member 26.

The probe unit as described above uses an abrasive paper such as a fine-grained sandpaper and a test device for a test object to polish the projections, so that the test object vacuum-adsorbed on the chuck top of the test device is inspected. The height of the projection relative to the body can be constant.

Such polishing can be performed, for example, by assembling a probe unit into a test head as shown in the figure, mounting the test head on a test apparatus, and then, in this state, the projection and the chuck top are first placed. A reference position for contact is determined, and then the chuck top and the probe unit are separated from each other by at least the thickness of the abrasive paper to be used. Paper tag assessment (10
This can be performed by applying an overdrive of about 0 μm.

When the above-described polishing method is used, each probe area is warped in an arc shape, and the polishing paper is rubbed while the projections are in contact with the polishing paper. The height position of the tip of the protrusion with respect to the inspected object becomes the same.

In each of the above embodiments, the slit 28 penetrating the probe unit in the thickness direction is formed. However, the slit 28 penetrating only the spring member 26 may be formed in the spring member 26. A slit is formed in the spring member 26 and the non-conductive member 22 so as to penetrate the spring member 26 in the thickness direction and not to penetrate the non-conductive member 22 in the thickness direction. Alternatively, the slit may not be formed.

Also, instead of using a projection having a hemispherical tip and a columnar main body integrally formed therewith, a projection having another shape such as a cylinder, a prism, a cone, a pyramid, or the like may be used. You may. In this case, it is preferable that the projection is covered with the protective layer in a state where only the tip of the projection 34 projects.

The spring member 26 only needs to be present at least from the tip of the probe area 32 to the probe unit mounting portion 42 on the probe unit mounting body 42 when the probe unit is assembled to the test head. Therefore, unnecessary portions of the spring member 26 may be removed before assembling the probe unit to the test head.

However, unnecessary portions of the spring member need not be removed. Further, the length of the probe unit is changed from the tip of the probe region 32 to the probe unit mounting member 42.
The flexible flat cable may be electrically and mechanically connected to the probe unit when assembling it to the test head. Further, the size of the spring member may be set to the minimum necessary size from the stage of manufacturing the probe unit.

The present invention is not limited to the above embodiment. For example, the present invention can be applied not only to a probe unit used for testing an integrated circuit, but also to a probe unit used for testing or testing other flat test objects such as a liquid crystal display panel. The present invention can be applied not only to a probe unit using a probe unit for one test head, but also to a probe unit using one probe unit for one test head.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a probe unit of the present invention.

FIG. 2 is a longitudinal sectional view of a lobe region in the probe unit shown in FIG.

FIG. 3 is a sectional view taken along line 2-2 in FIG. 2;

FIG. 4 is a bottom view showing one embodiment of a test head using the probe unit shown in FIG. 1;

FIG. 5 is a sectional view taken along line 5-5 in FIG. 5;

FIG. 6 is a longitudinal sectional view of a probe area in a second embodiment of the probe unit.

FIG. 7 is a bottom view of the probe area shown in FIG. 6;

FIG. 8 is a sectional view taken along line 8-8 in FIG. 7;

FIG. 9 is a longitudinal sectional view of a probe area in a third embodiment of the probe unit.

FIG. 10 is a cross-sectional view taken along line 10-10 in FIG.

FIG. 11 is a longitudinal sectional view showing a modified example of the probe area in FIG. 9;

FIG. 12 is a longitudinal sectional view of a probe area in a fourth embodiment of the probe unit.

FIG. 13 is a sectional view taken along the line 13-13 in FIG.

[Explanation of symbols]

 20, 50, 60, 70 Probe unit 22 Sheet-shaped non-conductive member 24, 52 Wiring portion of wiring pattern 26 Sheet-shaped spring member 28 Slit 30, 56 Protective layer 32 Probe region 34, 54 Projection 62, 72, 74 , 76 Conductor layer 64, 78, 80 Electrical insulating layer 68, 72 Short-circuit member

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takeshi Inuma 2-6-1-8 Kichijoji Honcho, Musashino City, Tokyo Inside Nihon Micronics Co., Ltd.

Claims (5)

[Claims] 1. A sheet-shaped non-conductive member, a wiring pattern including a plurality of elongated wiring portions formed on one surface of the non-conductive member at intervals, and the other surface of the non-conductive member A sheet-like spring member disposed at least at a portion corresponding to one end of the wiring portion, and a conductive protrusion projecting from one end of each of the wiring portions to a side opposite to the spring member; A probe unit for testing a flat object to be inspected, comprising: a projection having a tip protruding; and an electrically insulating protective layer covering at least the wiring portion near the projection. 2. The probe unit according to claim 1, wherein the protective layer covers the protrusion and at least a portion of the wiring portion that functions as a probe element. 3. The probe unit according to claim 1, further comprising at least a plurality of slits formed in said spring member to form a plurality of elongated probe regions including at least one of said wiring portions. 4. The probe unit according to claim 1, further comprising one or more conductive layers disposed in said protective layer. 5. A second wiring pattern including a plurality of elongated second wiring portions formed on the protective layer so as to extend in parallel with the wiring portions, and a second wiring pattern extending from one end of each of the second wiring portions. A conductive second protrusion protruding to a side opposite to the spring member; and an electrically insulating property surrounding the second protrusion and the second wiring portion in a state where a part of the second protrusion protrudes. The probe unit according to claim 1, 2, or 3, further comprising a second protective layer.